Rude behavior

Question
My boyfriend and I have the sweetest 21 month old female silver toy poodle. She has a tremendous personality, and is a joy in almost every way- she has rude behavior towards people/children/other dogs that she does not know. We eventually want to get children, so this will definitely turn into a problem. When we take her to the dog park, she always snarls at other dogs, and sometimes even snaps at them, hardly ever warming up to any of them. She is the same way around people she does not know, but eventually warms up to them once they show her love. Except for children, she wants NOTHING to do with them. I have to keep her away from my nieces because I am afraid of what she may do. I think she is scared of them. How can we help her become more comfortable around trusted people and not be so mean to other dogs? I know she can be fine with them because we live with my mother's border collie and the two of them get along great.
Thanks for your help,
Lesley  

Answer
Hello Lesley,
What you need to do with your dog is re-introduce her to children so that she sees that they are just as friendly and will give her love as the adults.  Lots of dogs don't understand "small people" because they have grown up around adults.  
When you introduce her to children, either pick her up so that she is more on their level at first, or have them get down on their level to pet her.  Make sure that you have some little treats with you also so that they can give her something good.  If she growls or tries to nip, lay her on her side with her head on the floor and make her submit to both you and the children.  By doing this, you let her know that she has to submit to you as her Boss, and to the children because the Boss says so.  
If you think that she will be alright with your nieces, let her meet them.  Let them help with her if possible.  Allow them to feed her, take her for a walk with you, or throw toys for her (if shes into that).  Build it up so that they don't do that all in one day, but enough so that she sees that they are her friends.  

At the dog park, you may want to try taking her out there and keeping her on leash for several times.  If you use a long leash, you can let her play or run a bit, but with the leash you can correct her if she gets snappy.  You might also try taking her out to the park with your mothers dog if she gets along or plays with him/her.  

Give this a try and see if it helps you some.  If you have further questions or concerns for me, please feel free to ask.

Thanks for using AllExperts.com,
Kim